I have had many coffee roasting experiences in the last 12 years since I first created my own commercial roaster and started roasting professionally. Here are a couple.
12 years ago I was living in the Little Applegate Valley in southern Oregon in a beautiful home on 20 acres of forest. It was still and quiet, and I had created my own 5 lb. commercial roaster that I used to roast daily. I had developed a small customer base in which I roasted and delivered my whole bean coffee, as well as made cold brew coffee that I bottled and also delivered.
My roaster was located next to my garage under an awning that protected it from rain and snow in the winter. The sides of my roasting area were open to allow the smoke to escape (there is quite a bit of smoke created from burning chaff when roasting 5 lbs. of coffee at a time). Because the property was so quiet, I could easily hear the cracking of the coffee without having to be right next to it. Each roast took about 45 minutes to complete so I often would start the roast and then leave to work on some other things and come back when I first started to hear the cracking.
One time, I got so involved in another project I was doing that I completely forgot about the roast. When I remembered, I rushed to the garage to see flames 4 feet high starting to catch the wooden garage on fire! Luckily a hose and water source were nearby and I was able to put the fire out before major damage had occurred! This is what is known as a “bean fire”, and happens when the coffee beans have roasted well past the cracking stage, the oils have been exposed, and the coffee starts to catch on fire. That was very scary and was something that I never wanted to repeat again! That was brutal and accidental, for sure!
For this next occurrence I would add surprising to brutal and accidental. This occurred in Bali, Indonesia where I relocated after leaving southern Oregon. My commercial roaster design had evolved and I was creating a larger more durable machine in Bali. This new machine had a capacity of 8 kilos (17.6 lbs.) and was made entirely of high grade stainless steel. I made this roaster to order and shipped them around the world to different countries. It was a very affordable roaster for Cafe’s that wanted to roast their own coffee but had a limited budget. I had contracted with a factory in the city, Denpasar, that specialized in stainless steel fabrication. For every roaster that we produced I would do a final inspection and test roast before shipping to the customer. The roasted coffee I used in the test roast I would return to my staff at my 3 Cafe’s in Ubud, for their use. This was perfectly roasted 100% Arabica coffee and I did not want ANY going to waste!
90% of the time I had no problems with the test roast and there were no changes that needed to be made. However, one time, a few years ago, during the test roast there seemed to be a problem. One side of the roaster was getting hotter than the other side and it was causing the coffee beans on that side to roast darker. I had never encountered this problem before and looked at every possibility but still could not figure it out. After three tries of roasting, then cooling, then roasting again, I gave up and determined that the 8 kilos were ruined and had to be thrown out, because the roast was so uneven. Finally, after remeasuring everything on the roaster I found out the problem. The heating element was not level, it was higher on one side which meant the flame on that side was closer to the coffee in the drum causing the coffee on that side to roast quicker. I asked the workers how could this have happened, and the reply I got was that a new worker had made this particular roaster instead of the guy that usually made it. Angry and frustrated, but satisfied that the problem was solved, I took the uneven roasted coffee back to my staff at my Cafe’s.
When I returned this bad batch of coffee and explained the problem, the staff seemed not too concerned. I told them to throw the batch out but they did not want to and had a different idea. They said they would roast this same batch again the next day (most of it was still a lighter roast), even it out, and then make cold brew with it. I was shocked that they would consider roasting the coffee again after it was already roasted and cooled (several times) but they assured me that this had happened before when the guy that did all of the roasting had run out of propane (the heat source for the flame), and had to get another tank of propane after the roast had already cooled. I told them that I wanted to come back after the cold brew was made and taste it before offering it for sale to customers.
Two days later I returned to taste test the batch of cold brew that was made with the roasted, cooled, roasted again coffee. To my amazement, I could not tell the difference! I tasted 3 different batches of cold brew and they all tasted the same! This taught me how strong and resilient coffee is and how a bad roast (as long as it is not over-roasted) can be revived and used.
Accidental? Yes. Surprising? For sure!
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